Pallet/flip unit/gantry system

ABSTRACT

Industrial pallet has a body with an open bay, in which a work piece can be secured such that it can be worked on from either side of the pallet. An overhead gantry and/or flipping unit may be employed to move from station to station and/or flip the work piece itself or the work piece mounted in the pallet. Aside from the flipping unit, robotic moving and/or loading may be employed by the overhead gantry, which has two axes of motion only. Such components can be combined in a manufacturing system to make parts.

This claims benefits under 35 USC 119(e) of U.S. provisional patentapplication No. 61/201,689 filed on Dec. 12, 2008 A.D. The entirespecification of that application, to include its drawings of course, isincorporated herein by reference.

FIELD AND PURVIEW OF THE INVENTION

This concerns an open bay pallet, flip unit and/or overhead gantrysystem. The same may be employed in various production methods orprocesses such as with milling, grinding, electric discharge machining(EDM) processing, and other machining of a work piece to make a part.The part, for example, may be a steel detail for a progressive die.

BACKGROUND TO THE INVENTION

Manufacture of parts through machine cutting, milling, grinding and/orEDM processing is widely employed in industry. Aside from the veryexpensive and fairly rare proposition of milling a part in a tombstonepallet, often a part is milled, drilled and ground outside the confinesof a pallet. A pallet, however, is typically employed to hold the partfor EDM processing. Commercially available pallets for EDM processingtypically have receiver units that mount to the top surface of mountingrails on a work piece within the wire EDM machine. A drawback is thatEDM, for example, which is an efficient process otherwise, is limited tosmaller plate work without removal and subsequent re-installation of thework piece as well as re-calibration of the receiver unit, and the workpiece set up for EDM requires a very high degree of precision. Thisincreases the possibility of error as well as the time required inmanufacturing the part.

A typical manufacturing process for making steel details for progressivestamping dies, in which usually no two details are alike, may generallyentail manually setting up a work piece in a computer numerical control(CNC) machining center; performing the machining operation such asmilling, drilling, boring, counterboring, and so forth; sending the workpiece to a heat treating facility off premises for heat treating;performing multiple separate set up operations for readying the workpiece for grinding, each set up for one side of the work piece, which ishighly time consuming; subjecting the work piece to grinding, one sideper time; set up for EDM, which is generally the most time consuming ofsteps; and subjecting the work piece in a pallet to EDM processing.Manual movement of the work piece is usually carried out betweengrinding and EDM processing. Known robots that do this type of workoffer some level of automation, which improves upon the manualoperations otherwise needed. However that may be, known overall systemsare typically floor mounted, which prevents workers from access to muchif not most of the machine tool space, which sits on the floor, whilerunning; thus, in other words, the workers get “caged in” in the entryarea to any robotics system. In addition, these robotic systems oftenprevent access to most of the machine tools while in operation. Also,the floor-mounted nature of the known systems limits the number ofmachine tools that can be tied together, and are not easily expandable,if at all. The robots that service the known systems generally have ahigh number of axes of motion, and yet the end result of their motionsare often limited, especially since they service only one or two machinecenters, which is not cost effective.

It would be desirable to ameliorate problem(s) in the art, and desirableto improve manufacturing efficiency. And, it would be desirable toprovide an alternative to the art.

A FULL DISCLOSURE OF THE INVENTION

Provided hereby is an industrial pallet comprising a body with an openbay, in which a work piece can be secured such that it can be worked onfrom either side of the pallet. An overhead gantry and/or flipping unitmay be employed to move from station to station and/or flip the workpiece itself or the work piece mounted in the pallet. Aside from theflipping unit, robotic moving and/or loading may be employed by theoverhead gantry, which has two axes of motion only. Such components canbe combined in a manufacturing system.

The invention is useful in manufacture of parts.

Significantly, by the invention, the art is improved in kind. A viableand efficient alternative is provided. The open bay pallet provides forsubstantially increased versatility and greater capacity inmanufacturing capability; parts, including the steel details forprogressive stamping dies, can be worked from above and below thepallet, and thus do not need to be moved, repositioned, and recalibratedas with known pallets; grinding and EDM processing can be carried outwith one setting of the work piece in the open bay pallet; and manyother features not possible to be manufactured in a part heretofore canbe provided hereby. The open bay pallets can have the capability to belocked down, in other words, precision loaded and clamped, into thepredetermined machine tool such as a grinder, and EDM processer, and soforth, or set up station receiver, and maintain access from the two mostimportant sides, top and bottom. This dual sided access of the open baypallet allows automatic grinding on both of these sides of the workpiece. The lock down system can integrate with an EDM processing machinein a sub-level style, which does not interfere with normal operation ofthe machine, and the sub-level locking/locating system maintainsflexibility of the EDM processing machine and minimizes set upoperations and time. This provides for operation of the EDM processingmachine in its standard fashion without the open bay pallet, or with theopen bay pallet, with little or no change over time associated with theswitch on account of the sub-level table surface locking system. Thus,since both sides of the work piece can be ground in the open bay pallet,and that same pallet can be moved to the EDM processing machine, theoverall process for that can be reduced from three set up operations,i.e., one for each side of the work piece at the grinder and one at theEDM processing machine, to a single set up operation. This further meansthat the single set up operation hereby does not require the accuracyotherwise required at EDM set up; it only requires locking the workpiece into the locating mechanism in the open bay pallet. This moresimple approach requires less skill on the part of the operator, iseasier to teach to him, and takes less time than either of the prior artset up operations. Also, employment of this approach allows simpleverification that the EDM process is set up properly, which ensures ahigher level of quality control and reliability in the EDM process.Since the work pieces can be ground in place in the open bay pallet,even including flipping with the flipping unit, there generally is noneed for adjustment of the work piece before being taken to the EDMprocessing station, which ensures a more consistently accurate set up ofthe work piece than in the manual method of setting up for the EDMprocessing, which is done after grinding. The open bay pallet can takeadvantage of special notches and locating features such as located onfront and back edges of the pallet, as well as corresponding notches inthe work piece, which are automatically milled into the work piece atthe milling stage of the manufacturing process, typically beforegrinding or EDM processing. The automation of this process amelioratesif not substantially eliminates most if not all the possibility of errorin work piece set up operations, and also makes the amount of timerequired to mill the locating features minimal. The milling automationis provided by an integrated design system. Such locating featuresmilled into the open bay pallet and the work piece are also used in thework piece in the automated milling process, which allows the presentsystem to provide for automatically flipping the work piece over itselfor when mounted in the open bay pallet, which heretofore was not knownor feasible. These locating features milled into the work piece alsoenable storage of the work piece after CNC milling and flipping, and itsretrieval in an accurate and precise manner. Because these machined workpieces are not in pallets, with the open bay pallets typically cominginto play for the grinding and EDM processing operations, many more workpieces can be stored with the practice of the present system than in aprior art tombstone system because storage of a milled, drilled, and soforth machined work piece in the present system is done without anypallet before grinding or EDM processing, which contributes further toreduced costs and increased capacity of the system. The open bay palletscan be employed with work pieces that do not have the quick locatingfeatures milled into them; thus, the versatility of the system isincreased. The open bay pallets have the capacity to be adjustable withrespect to pitch of the clamp bar mechanism for leveling of its mountingmember, for when no milled locating feature is provided in the workpiece, or fixed or locked with respect to pitch, say, at the same levelas the clamp bar housing of the pallet, for when the work piece is takenthrough grinding and EDM processing, normally including the milledfeature having work piece, depending on which mode of operation forwhich they are being used. For instance, if the work piece needs to beground and subject to EDM processing, i.e., it is a new work piece, thenthe fixed or locked version will be normally employed. On the otherhand, if the work piece is, for example, a detail that has already beenprocessed through grinding and/or EDM processing steps and afterremoving from the system it is desired to be subject another time to EDMprocessing such as to make changes to the work piece such as a designchange, a necessary adjustment to a dimension, and so forth, then theopen bay pallet can be used in adjustable mode in order to “level” thealready ground part to the EDM processing machine. The present systemcan include automatic flipping of the open bay pallet or the milled workpiece with locating notches by a 180-degree rotation by use of theflipping unit, which may be on the gantry, which allows the noted accessto the work piece from either side, top or bottom, for purposes ofgrinding. Also, grinding of work piece such as a steel detail secured inthe open bay pallet avoids effects normally associated with grinding ona magnet, in which case the vertical magnetic force can be so strong asto act on the work piece and deform it so that the finished work piecemay not be as truly accurate or precise in final dimensions as desired.The present system can include a wash down station to rinse off grindingfluid such as between grinding and EDM processing. An air blow offstation located any suitable place in the system, say, near the grindingstation, can eliminate water pooling on the open bay pallets and workpieces while they are in storage. A probe built into the present system,located, for instance, with a grinding machine housing spindle column,can be provided so that the automatic grinding provides for a moreprecise part in that the ground dimensions are measured with the probeand adjustments are automatically made to ensure that the parts arecompleted accurately and with a very high level of tolerance with nodirect human intervention. The present system can be employed also toload parts into a CNC milling machine and automatically run work pieces.Because the present system can be run in this fashion, it avoids theneed to purchase and operate an expensive pallet pool style machiningcenter, which can cost three to four times as much as that of a standalone machining center. The present system is also capable of deliveringa multitude of tools to the CNC machining center, and due to a uniquetool storage and retrieval subsystem, which operates similar to the workpiece storage system, the number of tools that may be stored is greaterthan in most commercially available systems, which makes for efficientovernight machining of a wide mix of work pieces with the presentsystem. A pallet could be modified with tool receiving stations toreceive the tools and have them stored there. A computer queue subsystemcan control the robot as well as the milling machine, the grindingmachine, the EDM processing machine, plus the storage, and downloadingof CNC programs to those machines. Computer controlled automation thuscan be nearly all-encompassing in manufacturing with the present system.The overhead gantry storage is highly space efficient. The system canenable unattended around the clock operation of milling, grinding andEDM machines. Because it is so highly space efficient, it becomesfeasible for one robotic system to service more machine tools within theone system. The system can use only two axes of movement only, whichreduces cost and complexity, and increases reliability.

Numerous further advantages attend the invention.

The drawings form part of the specification hereof. With respect to thedrawings, which are not necessarily drawn to scale, the following isbriefly noted:

FIG. 1 is a flow chart representing an example of processing that can becarried out with the present manufacturing system. On the left hand sidecolumn is shown some illustrative steps in a milling procedure throughheat treat processing, and on the right hand side column is shown someillustrative steps in grinding and EDM processing.

FIG. 2 is a top plan view of an assembly including an open bay pallet,overhead gantry robot, flipping unit, and so forth, especially forgrinding and EDM processing.

FIG. 3 is a right side plan view of the assembly of FIG. 2, taken alongarrow 3.

FIG. 4 is a front plan view of the assembly of FIG. 2, taken along arrow4.

FIG. 5 is a top plan view of an open bay pallet, which can be employedin the assembly of FIG. 2. The pallet is adjustable as to pitch.

FIG. 6 is a side plan view of the pallet of FIG. 5, taken along arrow 6.

FIG. 7 is a front plan view of the pallet of FIG. 5, taken along arrow7.

FIG. 8 is a front, top exploded view of a pallet such as of FIGS. 5-7,plus having locking hole and plate features for fixing or locking theadjustable pitch pallet flat.

FIG. 9 is a front, top view of a set up station in the assembly of FIGS.2-4.

FIG. 10 is a right side, top perspective view of the open bay pallet ofFIG. 8 on the set up station of FIG. 9.

FIG. 11 is a top perspective view, taken from the front, right, of theopen bay pallet and set up station as in FIG. 10 having a work piece inthe pallet.

FIG. 12 is a right side plan view of a portion of the assembly of FIG.2, to include its overhead gantry robot.

FIG. 13 is a perspective view of an assembly such as shown in FIG. 2,taken from the front, right side, looking up at its overhead gantryrobot.

FIG. 14 is another perspective view of the assembly in FIG. 13.

FIG. 15 is another perspective view of the assembly within FIG. 13,taken from the front, left side.

FIG. 16 is a front view of a pair of opposing lift arms of an overheadgantry robot.

FIG. 17 is a top, plan view of a set of lift arms moving into positionto lift or release an open bay pallet.

FIG. 18 is a perspective view, taken from the rear, right hand side ofthe assembly of FIG. 2, with its overhead gantry robot ready to lift orrelease a pallet at a set up station.

FIG. 19 is a perspective view, taken from the front, bottom, looking upat a pallet in overhead storage in the assembly of FIG. 2.

FIG. 20 is a right side perspective view of a work piece in an open baypallet being operated on at a grinding station in the assembly of FIG.2.

FIG. 21 is a front schematic view of a flip unit coming into position tosecure a pallet or work piece for turning it over such as may occur inan assembly as of FIG. 2.

FIG. 22 is a perspective view, taken from the right hand side lookingup, at a flip unit in the assembly of FIG. 2, at full extension.

FIG. 23 is a front, right side perspective view of an EDM station asfound in an assembly such as of FIG. 2.

FIG. 24 is a front, top perspective view of an EDM work table in FIG.23.

FIG. 25 is a perspective view, taken from the top, front, right side, ofEDM processing of a work piece in an open bay pallet in the assembly ofFIG. 2.

FIG. 26 is a top plan view of a portion of an assembly such as that ofFIG. 2, in which work piece and tool storage is provided.

FIG. 27 is a right side plan view of the storage subassembly of FIG. 25.

The invention can be further understood by the detail set forth below,which may be read in view of the drawings. As with the aforementionedmatter, such is to be taken in an illustrative and not necessarilylimiting sense.

With more particular respect to the drawings, work piece 9, which may beof any suitable size—for example, pertaining to length by width ininches, a 4×4 work piece 9A, a 4×6 work piece 9B, and a 4×8 work piece9C—and material such as of metal, plastic, ceramic or composite, forexample, of steel, which may be provided with a little, say, a ⅛-inchdiameter blind positioning hole 9P in its bottom centered from side toside at 0.150 of an inch from a front side, and/or with opposing V-notchgrooves or holes 9V, and which can be operated on with portions ofassembly 100, say, to make a steel detail for a progressive die. Theassembly can include movement/storage system superstructure 10; overheadgantry robot 20/30, with its gantry robot truck 20 and gantry robot liftunit 30; open bay pallet 40; and flipping unit 50. The assembly 100 caninclude, in general, under the superstructure 10 such stations as set upstation 60; grinding station 70; and EDM station 80. Also, the assembly100 can have under it superstructure 10 or outside its confines andfield of operation milling and/or milled work piece and/or tool storagestation 90. In general, the assembly 100 provides movement from stationto station for the work piece 9 and pallet 40 by its overhead gantryrobot 20/30 along two axes: back and forth, horizontally, along a firstaxis, designated, “x,” and up and down, vertically, along a second axis,designated, “z.” Such stations as the stations 60, 70, 80, 90 and soforth may be positioned at any convenient position within or in relationto the assembly 100, and may be reconfigured during the lifetime of theassembly 100 according to immediate need. More than one of each of thestations 60, 70, 80, 90 may be employed in the assembly 100, or one ormore of such stations may be left out of the assembly 100 or bypassedduring its operation on a particular work piece 9. Generally, however,the set up station 60 would be present under the superstructure 10, andone or both of the grinding and EDM station(s) would be present underthe superstructure 10 as well.

The movement/storage system superstructure 10 can include verticalsupport posts 11, say, made from drawn structural steel, which may haveattached floor-mounted cross-members 11F; diagonal support beams 12;upper rail set 13, say, made from drawn structural steel and provided inan opposing parallel pair, along which the overhead gantry robot 20/30can move horizontally; outside gantry distance controlling chain/cableaccommodating rail 13A; stationary upper rail rack gear 14; lower railset 15, say, made from drawn structural steel and provided in anopposing parallel pair, for providing storage areas and fortifying thesuperstructure; and lower rail cross-members 16 for providing storageand fortifying the superstructure as well. The superstructure 10 can beany suitable length depending on the type and number of machines andstorage for the desired capacity of the assembly 100.

The overhead gantry robot 20/30 includes connected components of thegantry robot truck 20 and gantry robot lift unit 30. The gantry robottruck 20 provides computer controlled, precision horizontal motion alongthe x-axis, and includes roller guide 22; horizontal travel flexiblecable/chain carrier 23, which can rest upon the rail 13A; and horizontalpinion gear 24, which is powered by a motor, rotates in a precisemanner, and engages the stationary upper rail rack gear 14. The gantryrobot lift unit 30 provides computer controlled, precision verticalmotion along the z-axis, and includes outer guide rail 31, which can beprovided with minimal friction roller guide 31A; z-axis lift member 33,which is guided by the rail 31 and roller guide 31A, and which is raisedand lowered through ball screw 34 powered by motor 34M; and lift hookassembly 35 connected to the lower extremity of the lift member 33,which may be provided in a set of two opposing, mirror image pairs andinclude lift hook finger 36 from an upper surface of which projects lifthook locating pin 39.

The open bay pallet 40 can be made of any suitable material such as asuitable metal, ceramic or composite, say, steel, and can include outerhousing 41, which can have outer lift bay area structure 41B and front41F and rear 41R portions, and may have as well flipping V-grooves orholes 41V front and rear, and be about open inside bay 42; adjustableclamp member 43, say, in a form of a bar, which may be provided withadjustable clamping pads 43C and/or horizontal groove 43G, into which asmall spacer such as a rod, ball and so forth may be inserted as well asbeing inserted into a corresponding groove of a work piece 9 andsqueezed with the bar 43, all for better holding the work piece 9, andwhich bar 43 can be provided with internal female threads so as to mounton a set of two parallel threaded rods 44 on opposite sides of the bay42, say, running from front to rear, which threaded rods 44 may bemanually rotatable and locked into position with nuts 44N so as toadjust and secure the front to rear position of the bar 43; and clampingknob/net pad 45 to control necessary height, which may be provided insymmetric sets, even top and bottom; and locating pilots 46. The pallet40 may be equipped with inner pivotable housing 47 that is separatedfrom the outer housing 41 with slit 47S yet connected with living hinge48 so that pitch of the inner housing 47 may be adjusted by z-axis pitchscrew adjusting unit 48Z with a particular work piece 9 in mind; andperhaps level pitch locking assembly 49, which can include plates 49Pand screws 49S, so as to lock up at a level pitch such that the entiretop surface of a pallet 40 with its outer and inner housings 41, 47 goesalong the same plane if desired. The pallet 40 with or without the workpiece 9 is moved by the overhead gantry robot 20/30 by having the set oflift hook fingers 36 lowered into position in the outer lift baystructure 41B areas lower than the pallet 40, moved horizontally underthe pallet 40 in the outer lift bay structure 41B areas so that the lifthook locating pins 39 align with and enter into corresponding locatingholes 49Z in undersides of the outer lift bay structure 41B areas withlifting of the robot 20/30 to position the same, and then substantiallylifted up and transported in the assembly 100.

The flipping unit 50 includes rotating body 51, which is suitablypowered, say, by pneumatic action. Stationary V-notch points 52 are atan end of the rotating body 51; and movable V-notch points 53 are atextremities of extension arms 53A of freely rotating body 53B. TheV-notch points can engage the work piece V-grooves or holes 9V or thepallet V-grooves or holes 41V to provide for precise and secure180-degree flipping.

The set up station 60 can include receiver net pads 61 and left-rightcentering unit 62, which may include block 62B insertable into frame62F. The insertable block 62B has upstanding positioning pin 62P to gointo the positioning hole 9P in the work piece 9. Set up may begenerally manual, with the set up work piece 9 in the pallet 40 thenbeing moved automatically by the elevated gantry robot 20/30 for storageand operation within the assembly 100.

The grinding station(s) 70 perform(s) grinding and associated tasks.

The EDM station(s) 80 may include table 80T. It perform(s) EDMprocessing.

The milling and/or milled work piece and/or tool storage station 90performs its assigned tasks, and it may be positioned under thesuperstructure 10 of the assembly 100 or outside its confines and fieldof operation. Work piece 9 and tool 99 storage and retrieval under theconfines and field of operation of the superstructure 10 can employ thex-axis and z-axis movement provided by the overhead gantry robot 20/30plus y-axis horizontal movement provided by a table precisely movablefrom side to side, upon which the work pieces 9 and tools 99 can bestored in an array recognized by CNC center activity. Receptacles forthe tools 99 can be provided.

The present invention is thus provided. Various feature(s), part(s),step(s), subcombination(s) and/or combination(s) can be employed with orwithout reference to other feature(s), part(s), step(s),subcombination(s) and/or combination(s) in the practice of theinvention, and numerous and sundry adaptations and modifications can beeffected within its spirit, the literal claim scope of which isparticularly pointed out as follows:

What is claimed is:
 1. An industrial pallet comprising a body with anopen bay, in which a work piece can be secured such that it can beworked on from either side of the pallet, which includes: an outerhousing; an adjustable clamp member within the outer housing so as to bewithin the open bay of the pallet, which can hold the work piece in theopen bay of the pallet; an inner pivotable housing that is separablefrom yet connectable with the outer housing; a z-axis pitch adjustingunit such that pitch of the inner housing can be adjusted by the z-axispitch adjusting unit; and at least one of the following features (A, B):(A) an outer lift bay area structure in the outer housing; and (B) aclamping knob/net pad to control necessary height in operation.
 2. Thepallet of claim 1, wherein the outer housing includes flipping V-groovesand/or holes, front and rear; the adjustable clamp member is in a formof a bar, which is provided with adjustable clamping pads and ahorizontal groove, into which a small spacer can be inserted as well asbeing inserted into any corresponding groove of the work piece andsqueezed with the bar to better hold the work piece, and which bar isprovided with internal female threads and a set of two parallel threadedrods and nuts on opposite sides of the open bay, with the threaded rodsrunning from front to rear and which threaded rods can be rotated andlocked into position with the nuts so as to adjust and secure the frontto rear position of the bar; the clamping knob/net pad is provided insymmetric sets and includes associated locating pilots; the innerpivotable housing is separated from the outer housing with a slit andconnected with the outer housing with a living hinge, and the z-axispitch adjusting unit includes a z-pitch adjusting screw.
 3. The palletof claim 2, which includes a level pitch locking assembly, which canlock up at a level pitch such that a top surface of the pallet with itsouter and inner housings can go along one plane.
 4. The pallet of claim1, wherein feature A is present.
 5. The pallet of claim 1, whereinfeature B is present.
 6. The pallet of claim 1, wherein both features Aand B are present.
 7. An industrial pallet comprising a body with anopen bay, in which a work piece can be secured such that it can beworked on from either side of the pallet, designated as a first side anda second side, between which extends an axis designated as a z-axis,which includes an outer housing; and an adjustable clamp member withinthe outer housing so as to be within the open bay of the pallet, whichcan hold the work piece in the open bay of the pallet, wherein: theadjustable clamp member includes means for applying squeezing pressureto the work piece substantially perpendicular to said axis; and at leastone of the following features (A, B) is present: (A) the adjustableclamp member includes a bar, and said means includes a set of parallel,threaded rods; and (B) the pallet includes an inner pivotable housing,which is separable from yet connectable with the outer housing, and az-axis pitch adjusting unit such that pitch of the inner housing can beadjusted by the z-axis pitch adjusting unit.
 8. The pallet of claim 7,wherein feature A is present.
 9. The pallet of claim 8, wherein the workpiece can be secured such that it does not move with respect to thepallet.
 10. The pallet of claim 9, which is such that the work on thesecured work piece can be at least one of grinding and electricdischarge machining processing.
 11. The pallet of claim 8, wherein thework piece is such that it can be made into a detail for a progressivestamping die.
 12. The pallet of claim 7, wherein feature B is present.13. The pallet of claim 12, wherein the work piece can be secured suchthat it does not move with respect to the pallet.
 14. The pallet ofclaim 13, which is such that the work on the secured work piece can beat least one of grinding and electric discharge machining processing.15. The pallet of claim 12, wherein the work piece is such that it canbe made into a detail for a progressive stamping die.
 16. The pallet ofclaim 7, wherein both features A and B are present.